Hillary Clinton was “reckless and careless” to engage in discussion about an Iranian nuclear scientist in an email hosted on her private server, Sen. Tom Cotton said.

Iran confirmed on Aug. 7 that the nuclear scientist, Shahram Amiri, who gave information to the U.S. about Teheran’s nuclear program, was hanged for treason. He was convicted of spying charges in a death sentence case that was upheld on appeal, according to the Associated Press.

Shahram Amiri. /AFP

“I’m not going to comment on what he may or may not have done for the United States government, but in the emails that were on Hillary Clinton’s private server, there were conversations among her senior advisers about this gentleman,” Sen. Tom Cotton, Arkansas Republican, said on “Face the Nation” on Aug. 7.

“That goes to show just how reckless and careless her decision was to put that kind of highly classified information on a private server. And I think her judgment is not suited to keep this country safe,” he said.

A spokesman for Iran’s judiciary said Amiri had “provided the enemy with vital and secret information of the country. This person who had access to the country’s secret and classified information had been linked to our hostile and No. 1 enemy, America, the Great Satan.”

Amiri disappeared while on a religious pilgrimage to Saudi Arabia in 2009, but resurfaced a year later in the U.S., where he visited the Iranian interest section of the Pakistani embassy and demanded to be sent back to Iran. While he told reporters that he was held against his will by both the Saudis and the Americans, U.S. officials said Amiri was receiving millions of dollars for information he provided about Iran’s nuclear program.

Amiri shows up in Clinton’s emails in 2010, nine days before he returned to Iran.

“We have a diplomatic, ‘psychological’ issue, not a legal one. Our friend has to be given a way out,” the email by Richard Morningstar, a former State Department special envoy for Eurasian energy, read, according to the Associated Press. “Our person won’t be able to do anything anyway. If he has to leave so be it.”